While EV Buses have a range of environmental and operational benefits, their heavier weight, when compared to internal combustion engine buses (eg diesels), does create some challenges for road infrastructure and maintenance.
Below we explore the weight difference between the two bus types, and potential impacts to the road network, along with mitigation measures. Enjoy!
Firstly, what is the weight difference between EV and Internal Combustion?
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Diesel Buses: A standard diesel bus typically weighs between 10 to 12 tonnes when empty, depending on its size, design, and capacity.
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Electric Buses: Electric buses are significantly heavier, often weighing between 12 to 15 tonnes when empty. This additional weight is primarily due to the large lithium-ion battery packs used to store energy for propulsion. The battery alone can weigh several tonnes, depending on the range and capacity required.
For comparison, this is heavier than a light duty truck and heavier than a full medium duty truck, but not as heavy as large semi trailers which can weight between 18 to 44 tonnes.
Why are EV buses heavier?
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Battery Packs: The large batteries required for EV buses add substantial weight compared to a diesel engine and fuel tank system. For example, a battery pack capable of supporting ranges of 250-300 km can weigh 2 to 3 tonnes or more.
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Chassis Reinforcement: To accommodate the heavy batteries, EV buses often require strengthened frames and chassis, which also contribute to the increased weight.
What are the impact to the road network?
Unfortunately there are a few potential impacts in both the short and long term that can adversely impact the road network. These include:
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Increased road wear and tear: especially if roads on key bus routes are not designed for high axle loads.
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Stress on bridges: this has potential to shorten life spans and also has the potential to impact bus routes.
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Drainage impacts: heaver loads impact drainage system and increase risk of flooding.
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Maintenance costs: increase in transport infrastructure maintenance.
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Reduced pavement lifespan: especially on older roads and where there are a higher frequency of bus movements.
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Alex load regulation challenges: changes to regulations may be required depending on the jurisdiction.
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Unintended consequences for other vehicles: potential impacts such as pot holes which impact both comfort and safety.
What are the mitigation measures for decision makers?
Despite these challenges, cities can take proactive measures to address road infrastructure issues associated with heavier EV buses:
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Focus on upgrading roads and bridges to withstand increased axle loads.
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Use high-performance construction materials with enhanced durability and load-bearing capacity.
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Implement advanced pavement design techniques, such as thicker layers or reinforced concrete surfaces.
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Explore distributed weight designs for EV buses to minimise concentrated load impacts.
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Increase funding for infrastructure maintenance and modernisation as part of EV bus adoption programmes. IF FUNDING IS AVAILABLE OF COURSE!!!
In summary, with an increase in EV Buses there is potential for impacts to the road network that will need to be managed. These can impact not only maintenance but also choosing bus routes - many Councils around the country are already looking into this.
Of course while there are mitigation measures, most of these come at a cost. And in a tighter budget environment this has the potential to impact options. Watch this space!
Wishing everyone a great week.
Andrew
P.S. The Bond Quote this week is "Shaken, not stirred" which has been a signature line since Goldfinger in 1964!
Hand picked for this article because of the potential impact 'shaking' to the road network!
Transit Trends · Andrew Collings, KA Advisory. Read and comment on the original on LinkedIn.
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